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14.COORDINATE MEASUREMENT
By performing coordinate measurements it is possible to find the 3-dimensional coordinates of the target based
on station point coordinates, instrument height, target height, and azimuth angles of the backsight station which
are entered in advance.
• EDM setting can be done in coordinate measurement menu.
Setting items: "33.2 Observation Conditions - Dist"
PROCEDURE 3-D Coordinate Measurement
The coordinate values of the target can be found by measuring the target based on the settings of the
instrument station and backsight station.
The coordinate values of the target are calculated using the following formulae.
N1 Coordinate = N0 + S x sinZ x cosAz
E1 Coordinate = E0 + S x sinZ x sinAz
Z1 Coordinate = Z0 + S x cosZ + ih - th
N0: Station point N coordinate
S: Slope distance
ih: Instrument height
E0: Station point E coordinate
Z: Zenith angle
th: Target height
Z0: Station point Z coordinate
Az: Direction angle
• Z (zenith angle) is calculated as 360° -Z when the telescope is in the Face 1 position.
• If not measured or the space is left blank “Null” will be displayed.
If station point Z coordinate is set to “Null” the observation result for the Z coordinate is automatically set to
“Null”.
PROCEDURE
1. Sight the target at the target point.
N
1
N
N
0
Z
1
Z
0
E
0
E
1
E
Slope
Distance
Zenith
Angle
Instrument Height
Azimuth Angle
Target Height
Target (N
1
, E
1
, Z
1
)
Instrument Station (N
0
, E
0
, Z
0
)
Horizontal Distance